Throttle closing isues
Having an issue about when engine gets warm.
Returning to idle under deceleration, engine rpm won't go back to idle when I remove my foot from pedal, it feels like it has some binding but when I'm turn of engine there is no binding in anyway, so it must be a adjusting/calibration issue, but any ideas what to adjust?? DFCO, decel rpm/iac ect ect.
I've tried Google about adjustments, but seems to be easy to find anything out it.
First, watch your TPS value. It should always return to 0.0 or maybe 0.5 when you let off throttle. If it is not then you would want to look at your linkage and or TPS sensor.
I believe your issue is related to the the IAC. Common tuning issue. Go into the idle control menu in the Pro Tuning section. Increase the value on IAC loop down. This will increase the speed the engine returns to idle.
Quote from Austin DeHaas on June 9, 2019, 2:47 pmFirst, watch your TPS value. It should always return to 0.0 or maybe 0.5 when you let off throttle. If it is not then you would want to look at your linkage and or TPS sensor.
I believe your issue is related to the the IAC. Common tuning issue. Go into the idle control menu in the Pro Tuning section. Increase the value on IAC loop down. This will increase the speed the engine returns to idle.
When I remove foot from throttle when it's cold it goes to 0.0/0.5 but when warm between 2.5-4.5
Your thoughts about linkage sounds right because when removing linkage with engine running there is some binding BUT then it should still be some binding after shutting engine down, and then there are NO binding at linkage.
IAC loop rate down is at 11.
IAC loop rate up is at 23
Decel rpm decay is at 10.6
Decel iac decay is at 0.7
Ok, check your butterfly alignment in the bore and also check to make sure the secondaries are closing fully. May need to adjust some there also.
I have an issue with one of my units where the throttle closes fully but the TPS will show 4 to 6. Seems to happen in hot humid weather. Only one other I have seen this happen too. It was on a mud truck. Fitech has scratched there heads. I have replaced the TPS a few times. Solves for a few months. May try a new harness next. Need to reach out to Riverside.
Quote from Austin DeHaas on June 9, 2019, 10:02 pmOk, check your butterfly alignment in the bore and also check to make sure the secondaries are closing fully. May need to adjust some there also.
I have an issue with one of my units where the throttle closes fully but the TPS will show 4 to 6. Seems to happen in hot humid weather. Only one other I have seen this happen too. It was on a mud truck. Fitech has scratched there heads. I have replaced the TPS a few times. Solves for a few months. May try a new harness next. Need to reach out to Riverside.
Have fun at riverside.
If you read what I write, you can see that it can't be the butterfly alignment because nothings wrong when I'm shot down the engine. Then I think the TPS seems more plausible and I have to check that.
How are my # at IAC and decay?
Suggestions for # to decrease ?
Your tuning values are not in play, if you have a TPS that is hanging. If your TPS is not going to zero or near zero, when you let off, then there is a linkage or sensor issue.
Quote from Austin DeHaas on June 10, 2019, 1:51 amYour tuning values are not in play, if you have a TPS that is hanging. If your TPS is not going to zero or near zero, when you let off, then there is a linkage or sensor issue.
Okay about the values.
When engine is warm and I remove foot from throttle TPS shows one time 2.5 other times 3.5, 4.0 ect. not the same value each time, but when I "hit" the throttle TPS goes down to 0-0.5.
If I when TPS reads ex. 4.0 stop at the side of the road and go to linkage there seems to be some resistance/binding but as soon I turn of the engine resistance/binding is gone, then I can start and drive for maybe 1/2-1 hour before problem appears again.
How do I test TPS for defects?
If the TPS is hanging should it be constant cold or hot?
I had a similar problem, a stronger throttle return spring solved it. The further I'd pull the cable, the less it would go back. Once I turned the truck off, it would reset the TPS. Just wanted to throw out a possible easy fix if you haven't already tried a stiffer spring. Sounds like your problem is a little more involved, though.
Good luck!